Audiphone earpiece



Jan. 30, 1940. CARLSQN 2,188,591

AUDIPHONE EARPIECE Filed April 16, 1938 INVENTOR. THOMAS J CARLSON ATTORNEY Patented Jan. 30, 1940 UNITED STATES PATENT OFFICE Application April 16,

4 Claims.

This invention relates to earpieces for audiphones, and has for its objects improvements in the construction of these devices which facilitate manufacture, assemblage and accessibility, and

5 provide for individual fitting to the ears of different persons.

Other advantages of the improved construction are extreme ruggedness combined with low cost of production, yet withal an earpiece giving a high quality of performance. Other advantages of the improved construction will appear in the following description and accompanying drawing;

In the drawing: Figure 1 is a general view of the completely assembled earpiece shown full size and attached'to its electric cord.

Figure 2 is a greatly enlarged vertical central section of the earpiece in position shown in Figurel.

Figure 3 is a plan view of the electro-magnet core piece. 1 Figure 4 is a perspective view of the core wind- Figure 5 is an end view of the base receptacle of Figure 2 as seen with the diaphragm cap, and retaining ring removed.

Figure 6 is a perspective view of a modified form of the cap of the device.

In further detail, my improved earpiece which is preferably made of alight metal, such as aluminum, though it may be made of Bakelite or any suitable plastic material if desired, comprises a base receptacle or cup I, formed with an enlarged open end covered over the open end by a flexible steel diaphragm 2, surmounted by a cap 3 held in place by a threaded marginal collar 4, while within the cup is a U-shaped iron magnet core formed with a fiat base 5 riveted at 6 to the bottom of the cup and provided withv two spaced pole pieces I, I, projecting upwardly to a point adjacent the underside of the diaphragm,

while wound about one of the pole pieces is a coil 8, the terminals of which are respectively secured.

whichv enters the 'cup through an opening Ill concha to be supported also at its margin by the 1938, Serial No. 202,479

tragus of the ear. The cap is belled outwardly above the diaphragm to form the usual sound box space X.

The special features of my construction include a cap member 3 formed with a hollow dome l2 with the.nipple threaded at its inner end and screwed into a hole drilled through the dome and tapped to suit. provides for drilling the hole at any of the angles A, B, C, D, etc. to suit the particular angle of the auditory canal of the ear being fitted after carefully ascertaining the correct angle, for I have found that there is a great difference in this angle in difierent persons ears and unless the angle of each ear is individually fitted, considerable discomfort ensues which detracts from the efficiency of the device, whereas when the canal angle is correctly provided for the user is hardly conscious of the mechanical presence of the device.

Instead of providing a dome to facilitate drilling at the ascertained angle, the cap may have an elevated hollow portion of the form shown in perspective in Figure 6, and wherein the cap is designated 3 and the hollow protuberance I2 shown here as generally triangular in form with the hypothenuse represented by a relatively wide curved wall I!" anywhere along the center line F-F of which the hole for the nipple may be drilled.

The cap 3 is formed with a marginal step or ledge l3 to receive an inwardly turned flange 4 of collar l4 so that the outer surface of the assembled collar and cap will be smooth and free from ridges to irritate the wearer, and the body of the cup is beveled oil as at l' to smaller diameter so as to fit within the concha and it is in this annular beveled area that the hole I is drilled.

The magnet is of one piece struck up out of V a piece of sheet iron to form a large, round, flat base which fits within the lower end of the cup to center it and is secured to the bottom by the rivets 6 as explained. This makes an easily centered unit of great rigidity.

The coil 8 is separately wound on a flat mandrel to the form shown in Figure 4, preferably of enameled wire with the first layer around a wrapping of thin insulating paper or fiber I4, and the remaining layers of wire each separated by a sheet of Cellophane l5, left projecting beyond the wire about a sixteenth of an inch at both ends and with the inner and outer terminals of the wires 8' and 8" brought to the upper end of the coil, and after which the coil is simply pushed down over one of the poles 1 as far as it This provision of a dome I will go, the projecting Cellophane insuring insulation at the lower end. The double electric 7 surface of the cup at opposite points as at It,

and the terminals of the coil are respectively soldered to the ends of the cord, and after pushing down in place the soldered connections will each lie against one of the tape patches l6, and are each covered with another tape patch II which is pushed tightly around the joint to gum itself securely to the patch below and surrounding metal to hold the joint firmly in place.

In Figure the wire joint at the right side of the view (that of wires 9' and 8') is shown resting against the first tape patch IE, but not yet covered with the upper patch l1, whereas the other joint is shown completed and covered as described. The assemblage of coil and wire ends fits snugly and resiliently over and between the .pole pieces so that it cannot come out or shake loose in use or rough handling,yet.is very easily pulled out if necessary to renew the coil or inspect the same.

Having thus described my improved audiphone earpiece, what I claim is:

1. In anaudiphone earpiece having a cup-like base receptacle closed by a diaphragm with a cap thereover forming a sound box, a hollow projection on the outer side, of said cap, and a tubular nipple secured at its inner end in a hole formed in said hollow projection, said hollow projection formed exteriorly with a curved surface to provide for drilling a hole at various angles therethrough with respect to the central axis .of the cup-like base receptacle for reception of said nippie.

2. In an audiphone earpiece having a cup-like base receptacle closed by a diaphragm with a cap thereover forming a sound box, a hollow dome on the outer side of said cap, and a tubular nipple secured at its inner end in a hole formed 5 in the outer surface of saidhollow dome, said hollow dome formed with a substantially hemispherical outer' surface to provide for drilling a hole at various angles therethrough with respect to the central axis of the cup-like base re- 10 ceptacle for reception of said nipple.

3." In an audiphone earpiece having a cuplike receptacle closed by a diagram with a cap thereover forming a sound box, an electro-magnet within said receptacle provided with a pair of spaced pole pieces projecting toward said diaphragm, an insulated magnetizing coil frictional- 1y slipped over one of said pole pieces, and a flexible double electric cord extending through an opening in the side of said receptacle having its 2 ends resiliently forced between said coil and the other pole of said core and respectively connected with the terminals of said coil. l

4. In an audiphone earpiece having a cup-like I receptacle closed by a diaphragm with a cap thereover forming a sound box, an eiectro-magnet within said receptacle provided with a pair of spaced pole pieces projecting toward said diaphragm, an insulated magnetizing coil frictionally slipped over one of said pole pieces, and a flexible double electric cord extending through an opening in the side of said receptacle having its ends resiliently forced between said coil and, the other pole of said core and respectively connected with the terminals of -said coil, a patch .36 of adhesive tape positioned against the inner side of the receptacle and against which the connections are respectively positioned, and a patch of adhesive tape covering each connection and secured to the patch below it. o

' THOMAS J. CARLSON. 

